Analysis of the genetic structure of the red spiny lobster
(Panulirus interruptus) population was conducted along
the Baja California Peninsula, Mexico. Samples for allozyme analysis came from
Ensenada, Punta Eugenia, Punta Abreojos, San Juanico, and Bahia Magdalena
(about 50 individuals each). Of 16 loci analysed, five were polymorphic
(95% criterion) in at least one subpopulation. A significant mean value
of FIS = 0.125 indicated
some subpopulations departed from Hardy-Weinberg expectations; increased
homozygosity was particularly evident for alleles
EST-2*b and LAP*a at
Ensenada and EST-2*c and
EST-4*c at San Juanico.
MeanFST = 0.101, which
included 99% criterion polymorphic loci, was significant
(P < 0.05), supporting a genetic structure throughout
the species’ geographical range. Pairwise heterogeneity and FST tests
showed no significant differences in allele frequencies between Punta Eugenia
and Punta Abreojos, but several pairwise comparisons among the other
locations, especially at the most variable loci, showed significant
differences, supporting a hypothesis of genetic differentiation of
P. interruptus into three subpopulations: southern,
central, and northern Baja California. Oceanographic processes, such as
semipermanent eddies south of Punta Eugenia that tend to retain phyllosoma
larvae, may help generate this pattern. The implications of these findings for
the management of the resource are also considered.
Deep-water bivalve mollusks collected during the TALUD XV cruise off the west coast of the southern Baja California Peninsula, Mexico